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We’ve just been looking at an advert for a Quooker in one of Elizabeth’s magazines. It’s a device which gives you instant boiling water on tap and is all the rage in the modern kitchen (so I am told). They are pretty expensive (about £700) so we won’t be installing one anytime soon.

Or maybe we should? After all one of the reasons for getting these devices is that it is very energy efficient. It costs 3p a day to run and that’s “a saving of up to 55% against a kettle”. That’s got to be good.

Hang on though.

If 3p a day is a saving of up to 55%, then presumably a kettle costs around 6p a day?
That would be a saving of 3p x 365 = £10.95 per year
So that means the tap pays back in slightly under 70 years.